399497279 has 4 divisors (see below), whose sum is σ = 412384320. Its totient is φ = 386610240.

The previous prime is 399497257. The next prime is 399497291. The reversal of 399497279 is 972794993.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 399497279 - 2¹⁶ = 399431743 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399497209) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6443474 + ... + 6443535.

It is an arithmetic number, because the mean of its divisors is an integer number (103096080).

Almost surely, 2^399497279 is an apocalyptic number.

399497279 is a deficient number, since it is larger than the sum of its proper divisors (12887041).

399497279 is a wasteful number, since it uses less digits than its factorization.

399497279 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12887040.

The product of its digits is 7715736, while the sum is 59.

The square root of 399497279 is about 19987.4280236353. The cubic root of 399497279 is about 736.4974969907.

The spelling of 399497279 in words is "three hundred ninety-nine million, four hundred ninety-seven thousand, two hundred seventy-nine".